Long Term Outcome after Therapeutic Hypothermia in Neonatal Hypoxic-ischemic Encephalopathy

Abstract

Purpose: Therapeutic hypothermia is known to improve neurologic outcomes in hypoxic-ischemic encephalopathy(HIE) newborns. To the best of our knowledge, no report exists on the long term neurologic outcomes of HIE newborns who received therapeutic hypothermia in Korea, and we decided to conduct a study to evaluate these outcomes. Methods: A chart review was performed for 154 patients who were diagnosed with HIE at the neonatal intensive care unit of Seoul St. Mary's hospital from April 2012 to July 2014. We compared newborns who have treated therapeutic hypothermia with newborns who have not due to more than 6 hours after birth. Outcomes were verified with magnetic resonance imaging (MRI), electroencephalogram (EEG), and neurologic assessment using the Korean Ages and Stages Questionnaires (K-ASQ), Infant Toddler checklist (ITC) at the outpatient clinic. Results: Among 154 newborns, 117 underwent the 18 month-neurologic examination. Among these newborns, 56 received therapeutic hypothermia treatment and 61 did not. At 18 month neurological examination, developmental delay was observed in six of 56 newborns with therapeutic hypothermia and seven of 22 newborns without therapeutic hypothermia (P=0.04). Conclusion: If therapeutic hypothermia is accompanied with early diagnosis, active neurologic status monitoring, and hemodynamic status monitoring, therapeutic hypothermia may be helpful for the prognosis of HIE in newborns. 서론신생아 허혈성 저산소뇌병증(hypoxic-ischemic encephalopathy; HIE)은 신생아 가사가 원인이 되어 호흡곤란, 근긴장도 저하, 의식변화, 원시반사 소실, 경련, 수유 장애 와 같은 이상 신경 행동학적 소견을 보이는 상태이다 1,2) . HIE로 진단된 신생아들의 사망 률은 높은 것으로 알려져 있다 1,2) . 또한 HIE는 인지, 행동, 기억 영역에서 발달 지연과 연 관 있다고 알려져 있다 1,3-5) . 저체온 치료(therapeutic hypothermia)는 허혈성 저산소 상태에서 손상 받은 신경 세포의 회복을 향상시키는 치료법이다 6,7) . 저체온 치료가 HIE 신생아의 사망률과 단기 신경학적 예후를 개선한다는 것은 과거 여러 연구를 통해 밝 혀졌으며, 장기 신경학적 예후에 대한 연구는 현재 활발히 진행되고 있다 1,5,[8][9][10] .